| package com.genersoft.iot.vmp.gb28181.event.alarm; | 
|   | 
| import org.jetbrains.annotations.NotNull; | 
| import org.slf4j.Logger; | 
| import org.slf4j.LoggerFactory; | 
| import org.springframework.context.ApplicationListener; | 
| import org.springframework.stereotype.Component; | 
|   | 
| import java.io.PrintWriter; | 
| import java.util.Iterator; | 
| import java.util.Map; | 
| import java.util.concurrent.ConcurrentHashMap; | 
|   | 
| /** | 
|  * 报警事件监听器. | 
|  * | 
|  * @author lawrencehj | 
|  * @author <a href="mailto:xiaoQQya@126.com">xiaoQQya</a> | 
|  * @since 2021/01/20 | 
|  */ | 
| @Component | 
| public class AlarmEventListener implements ApplicationListener<AlarmEvent> { | 
|   | 
|     private static final Logger logger = LoggerFactory.getLogger(AlarmEventListener.class); | 
|   | 
|     private static final Map<String, PrintWriter> SSE_CACHE = new ConcurrentHashMap<>(); | 
|   | 
|     public void addSseEmitter(String browserId, PrintWriter writer) { | 
|         SSE_CACHE.put(browserId, writer); | 
|         logger.info("SSE 在线数量: {}", SSE_CACHE.size()); | 
|     } | 
|   | 
|     public void removeSseEmitter(String browserId, PrintWriter writer) { | 
|         SSE_CACHE.remove(browserId, writer); | 
|         logger.info("SSE 在线数量: {}", SSE_CACHE.size()); | 
|     } | 
|   | 
|     @Override | 
|     public void onApplicationEvent(@NotNull AlarmEvent event) { | 
|         if (logger.isDebugEnabled()) { | 
|             logger.debug("设备报警事件触发, deviceId: {}, {}", event.getAlarmInfo().getDeviceId(), event.getAlarmInfo().getAlarmDescription()); | 
|         } | 
|   | 
|         String msg = "<strong>设备编号:</strong> <i>" + event.getAlarmInfo().getDeviceId() + "</i>" | 
|                 + "<br><strong>通道编号:</strong> <i>" + event.getAlarmInfo().getChannelId() + "</i>" | 
|                 + "<br><strong>报警描述:</strong> <i>" + event.getAlarmInfo().getAlarmDescription() + "</i>" | 
|                 + "<br><strong>报警时间:</strong> <i>" + event.getAlarmInfo().getAlarmTime() + "</i>"; | 
|   | 
|         for (Iterator<Map.Entry<String, PrintWriter>> it = SSE_CACHE.entrySet().iterator(); it.hasNext(); ) { | 
|             Map.Entry<String, PrintWriter> response = it.next(); | 
|             logger.info("推送到 SSE 连接, 浏览器 ID: {}", response.getKey()); | 
|             try { | 
|                 PrintWriter writer = response.getValue(); | 
|   | 
|                 if (writer.checkError()) { | 
|                     it.remove(); | 
|                     continue; | 
|                 } | 
|   | 
|                 String sseMsg = "event:message\n" + | 
|                         "data:" + msg + "\n" + | 
|                         "\n"; | 
|                 writer.write(sseMsg); | 
|                 writer.flush(); | 
|             } catch (Exception e) { | 
|                 it.remove(); | 
|             } | 
|         } | 
|     } | 
| } |